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CE/NFELDER �s.;gne ano;e.x;vnesowno�. assessment. Kleinfelder will additionally prepare a health and safety plan prior to the actual field assessment. Task 2 —Advancement of Push Probes The purpose of the push probe assessment will be to collect additional background groundwater information near 81 lots located along the southern and northeastern portions of the Site and near proposed Basin 2 (see Plate 2). OLWD has expressed interest in conducting multiple groundwater sampling events from these temporary well points presumably in the quarter in which the wells are initially installed (third or fourth quarter of 2013). These temporary well points are also proposed to be destroyed in the quarter they are installed as EHD does not typically allow temporary wells to remain installed for prolonged periods of time. The total proposed depths of the push probes are 25 feet bgs for cost estimating purposes, but the actual depth/s will be based on field observations of first encountered groundwater. Therefore, some borings may be deeper or shallower than 25 feet bgs. Kleinfelder proposes approximately two days of work and the advancement of seven push probes. Four probes are proposed to be spaced throughout the elongated strip area of LAA No. 7R, two probes in the northeast portion of the Site and one in the northwest corner of the Site. Former temporary well data TW-1 through TW-3 will be used to support the additional groundwater information that will be obtained. The actual push probe locations will be dependent on access, surface conditions, and potential interference with subsurface and above-ground utilities. Prior to the advancement of the push probes, the first 4 feet will be advanced by hand auger to assess potential underground utilities. Push probes will be advanced using a pneumatically- driven steel probe. Soil samples will be obtained by inserting a sample barrel lined with acetate liners into the probe. The sample barrel will be lowered to the desired sampling interval and driven into the soil. To reduce the potential for cross-contamination, core barrels and associated down-hole equipment will be cleaned prior to advancing each probe. Soil samples will be collected continuously during the advancement of the push probes at depths ranging from near surface to the proposed maximum depth of approximately 25 feet bgs. During the advancement of the borings, soil samples will be collected for lithologic classification based on the Unified Soil Classification System. Once the probe has been advanced approximately 10 feet below first encountered groundwater, a 1-inch diameter, 10-foot long screened PVC pipe attached to blank PVC sections will be lowered into the probe. The annular space between the PVC casing and the wall of the boring will be backfilled with engineered 2/16 clean sand to approximately 2 feet above the top of the perforated sections. Groundwater will enter the screened section under hydrostatic pressure, and samples will be collected using a small diameter polypropylene tubing attached to a cleaned stainless steel ball valve or a stainless steel bailer. New PVC screened and blank sections will be used at each probe location. Stainless steel bailers, ball valves, and other down-hole re-useable equipment will be decontaminated prior to use at each sampling location by stream cleaning or scrubbing in a non-phosphate detergent wash followed by a distilled water rinse. The groundwater samples will be collected and decanted directly into laboratory supplied containers appropriate for the requested analyses. After collection, the seven groundwater 124374.T1/ST013R0535 Copyright 2013 Kleinfelder